Field of the Invention
The present invention relates to a calibration method for a level sensing apparatus and an anti-interference method for plural level sensing apparatuses, and especially relates to a calibration method for a capacitance level sensing apparatus and an anti-interference method for plural capacitance level sensing apparatuses.
Description of the Related Art
The principle for the capacitance level sensing apparatus is as following. The measured material and the tank are deemed as an equivalent capacitor. When the sensing rod of the capacitance level sensing apparatus is covered by the measured material, the capacitance is generated, so that the circuit signal is changed. However, the accuracy of the capacitance level sensing apparatus is affected by a lot of factors and variables. Therefore, after the capacitance level sensing apparatus is arranged, the user has to adjust the capacitance level sensing apparatus by hands. It is inconvenient. Moreover, when plural capacitance level sensing apparatuses are used at the same time, the capacitance level sensing apparatuses interfere to each other. The accuracy of the capacitance level sensing apparatus is also affected by that.